1. Technical Field of the Invention
The present invention relates to a chain guide device which is provided in an engine for interlocking a crankshaft with camshaft, and the crankshaft with an attachment or auxiliary machineries.
2. Description of Related Art
A fixed guide and movable guide urged by tension adjusting means have heretofore been utilized in order to prevent chains from loosening and deflection in their rotational movement where a crankshaft is interlocked with a camshaft, and the crankshaft is connected with an oil pump and an attachment or auxiliary machinery such as water pump.
In a device disclosed in Japanese Published Unexamined Utility Model Application No.138435/1988, for example, there are arranged on both sides of a path of rotational movement of a chain 34 tension adjusting means 35 which provides a proper tension to the chain 34 that interlocks a crankshaft 32 with a camshaft 33 in an engine 31, and a pair of guide members 36a and 36b provided at the upper and lower portions for regulating the path of rotational movement of the chain 34 with further arrangement of fixed guide members 39a and 39b for regulating a path of rotational movement of a chain 38 which interlocks the crankshaft 32 with an attachment such as balancer shafts 37a, 37b provided on both sides of the crankshaft 32, and a position adjusting guide member 40 as shown in FIG. 4.
However, when the guide members 39a, 39b and 40 provided for the chain 38 are attached independent of the guide members 36a and 36b for the chain 34 provided for the camshaft 33 as described above, the number of parts is increased to eventually raise a manufacturing cost, and it further necessitates an additional space. In the case when only a fixed-type guide is used, there causes a disadvantage of making noise and in its durability since such an arrangement can not eliminate loosening of the chain. In order to solve such a problem, if an arrangement is made to provide the chain 38 with a tension by a movable guide, and if an arrangement is made to regulate the amount of movement of the movable guide, the construction of a device becomes more complicated to eventually raise a manufacturing cost and necessitates an additional space since a hydraulic or mechanical ratchet mechanism would need to be applied. Under such a construction, attachment or auxiliary machinery can not be disposed adjacent to the crankshaft 32, and the manufacture of a compact engine is obstructed.